Representation of dust sources remains a key challenge in quantifying the dust cycle and its environmental and climatic impacts. Direct measurements of dust fluxes from different landform types are useful in understanding the nature of dust emission and characterizing the dynamics of soil erodibility. In this study we used the PI-SWERL® instrument over a seasonal cycle to quantify the potential for PM10 (particles with diameter ≤10 μm) emission from several typical landform types across the Tengger Desert and Mu Us Sandy Land, northern China. Our results indicate that sparse grasslands and coppice dunes showed relatively high emission potentials, with emitted fluxes ranging from 10−1 to 101 mg m−2 s−1. These values were up to five times those emitted from sand dunes, and one to two orders of magnitude greater than the emissions from dry lake beds, stone pavements and dense grasslands. Generally, PM10 emission fluxes were seen to peak in the spring months, with significant reductions in summer and autumn (by up to 95%), and in winter (by up to 98%). Variations in soil moisture were likely a primary controlling factor responsible for this seasonality in PM10 emission. Our data provide a relative quantification of differences in dust emission potential from several key landform types. Such data allow for the evaluation of current dust source schemes proposed by prior researchers. Moreover, our data will allow improvements in properly characterizing the erodibility of dust source regions and hence refine the parameterization of dust emission in climate models.
|Original language||English (US)|
|Number of pages||13|
|Journal||Earth Surface Processes and Landforms|
|State||Published - Aug 16 2019|
Bibliographical noteKAUST Repository Item: Exported on 2022-06-10
Acknowledgements: This work was supported by the National Key R&D Program of China (2016YFE0109500, 2016YFA0600503) and the National Natural Science Foundation of China (41690111). We wish to thank Professor James King (Université de Montréal, Canada) for providing the PI-SWERL results in the Salton Sea, Dr Sagar Parajuli (King Abdullah University of Science and Technology, Saudi Arabia) for providing raster files of global sediment supply map and Drs Wancang Zhao and Xin Jia for their helpful suggestions on the paper. We gladly thank Jiang Wu, Yang Yu, Chenghong Liang, Yao Gu, Xi Chang, Jia Wan and Yu Ding for their support during PI-SWERL experiments in the field.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.